Colony Weight Research Articles

Penilaian Efektivitas Metabolit Sekunder Trichoderma harzianum dalam Menghambat Pertumbuhan Colletotricum capsici dan Cercospora capsici : Kajian In Vitro

The cultivation of chili plants is often faced with obstacles such as disease attacks, especially anthracnose disease caused by the fungus Colletotricum capsici and leaf spot disease caused by the fungus Cercospora capsici. This study aimed to determine the effective concentration of T. harzianum secondary metabolites (MSTh) in inhibiting the growth of Colletotricum capsici and Cercospora capsici in vitro. The experiments used various MSTh concentrations: 0%, 10%, 20%, 30%, 40%, and 50%. The research results found that administration of MSTh could inhibit the growth of Colletotricum capsici and Cercospora capsici in vitro. Giving MSTh at a concentration of 10% can significantly inhibit the growth of Colletotricum capsici and Cercospora capsici compared to without MSTh. The effective concentration indicated by the percentage value of inhibitory power and colony weight reduction is an MSTh concentration of 40% with a growth inhibition of Colletotricum capsici of 89.49% and an MSTH concentration of 50% with a growth inhibition of Cercospora capsici of 57.78%.

Enhancing Honey Bee Health: Evaluating Pollen Substitute Diets in Field and Cage Experiments.

Honey bees (Apis mellifera L.) play vital roles as agricultural pollinators and honey producers. However, global colony losses are increasing due to multiple stressors, including malnutrition. Our study evaluated the effects of four pollen substitute diets (Diet 1, Diet 2, Diet 3, and Control) through field and cage experiments, analyzing 11 parameters and 21 amino acids. Notably, Diet 1 demonstrated significantly superior performance in the field experiment, including the number of honey bees, brood area, consumption, preference, colony weight, and honey production. In the cage experiment, Diet 1 also showed superior performance in dried head and thorax weight and vitellogenin (vg) gene expression levels. Canonical discriminant and principle component analyses highlighted Diet 1's distinctiveness, with histidine, diet digestibility, consumption, vg gene expression levels, and isoleucine identified as key factors. Arginine showed significant correlations with a wide range of parameters, including the number of honey bees, brood area, and consumption, with Diet 1 exhibiting higher levels. Diet 1, containing apple juice, soytide, and Chlorella as additive components, outperformed the other diets, suggesting an enhanced formulation for pollen substitute diets. These findings hold promise for the development of more effective diets, potentially contributing to honey bee health.

Effects of common co-occurring pesticides (a neonicotinoid and fungicide) on honey bee colony health in a semi-field study

Multiple stressors are linked to declines of insects and important pollinators, such as bees. Recently, interactive effects of multiple agrochemicals on bees have been highlighted, including fungicides, which increase toxicity of neonicotinoid insecticides. Here, we use a semi-field study across two seasons in controlled foraging tunnels to test the effects of a field application of a commercial fungicide product with two active ingredients (pyraclostrobin and metconazole) applied at label rates. We also examine its interactive effects with the neonicotinoid insecticide clothianidin, at a conservative field-realistic dose of 2.23 ppb, on 48 honey bee colonies. We found combined effects of pesticide exposure, including additive 2.93-fold increases in mortality, and an additional effect of increased infestation levels of the ectoparasitic mite, Varroa destructor. Pesticide treatments also reduced colony activity, reduced colony weight, and increased sugar consumption of whole colonies. These findings indicate that typical sublethal exposure levels to common, co-occurring agrochemicals in the field significantly affect the health of whole honey bee colonies, highlighting an unintended consequence of increasing pesticide applications.

Bombus terrestris Prefer Mixed-Pollen Diets for a Better Colony Performance: A Laboratory Study.

Pollen is a major source of proteins and lipids for bumblebees. The nutritional content of pollen may differ from source plants, ultimately affecting colony development. This study investigated the foraging preferences of Bombus terrestris in regard to four pollen species, i.e., oilseed rape, wild apricot, sunflower, and buckwheat, under laboratory conditions. The results show that B. terrestris diversified their preference for pollens; the bumblebees mostly preferred wild apricot pollen, whereas sunflower pollen was the least preferred. The colonies fed on a mixed four-pollen diet, with a protein-lipid ratio of 4.55-4.86, exhibited better development in terms of the number of offspring, individual body size and colony weight. The colonies fed with buckwheat and sunflower pollens produced a significantly lower number of workers and failed to produce queen and male offspring. Moreover, wild apricot pollen had the richest protein content (23.9 g/100 g) of the four pollen species, whereas oilseed rape pollen had the highest lipid content (6.7 g/100 g), as revealed by the P:L ratios of wild apricot, sunflower, buckwheat, and oilseed rape, which were 6.76, 5.52, 3.50, and 3.37, respectively. Generally, B. terrestris showed feeding preferences regarding different pollens and a mixture of pollens, which ultimately resulted in differences in colony development. The findings of this study provide important baseline information to researchers and developers of nutritive pollen diets for bumblebees.

Comparative Study of the Effect of Pollen Substitute Diets on Honey Bees during Early Spring.

The nutritional quality of a colony significantly affects its health and strength, particularly because it is required for population growth in the early spring. We investigated the impact of various artificial pollen substitute diets on colony performance in the Republic of Korea during early spring, a critical period for colony health and growth. The colonies were provided with different diets, including the commercial product Megabee (positive control), our developed diet Test A, and four upgraded versions (Diet 1, Diet 2, Diet 3, and Diet 4) of Test A. The negative control group received no supplementary feed. Over 63 days, we observed 24 experimental colonies and assessed various parameters at the colony and individual levels. The results revealed that Diet 2 had the highest consumption and had the most positive impact on population growth, the capped brood area, colony weight, honey bees' weight, and vitellogenin levels. These findings suggested that Diet 2 is most attractive to honey bees and thus holds great promise for improving colony maintenance and development during the crucial early spring period.

Next-generation colony weight monitoring: a review and prospectus

Next-generation colony weight monitoring: a review and prospectus

Effect of Addition Sinbiotic Isolate Pediococcus pentosaceus Strain N6 and Cassava Peel on Immunity Organs and Total Microbes in the Small Intestine of Super Native Chicken

Factory feed is often added with antibiotics as a growth promoter. Giving synthetic antibiotics is very dangerous for health. This study aims to determine effect of addition synbiotic isolate Pediococcus pentosaceus strain N6 and cassava peel flour on the immune organs and total microbes in the small intestine of super native chickens. This research was conducted in Pancur Batu from September - December 2022. The design used was a completely randomized design (CRD) with 4 treatments 5 replicates so that 20 experimental units were obtained. The super native chicken used were 100 DOC. The treatments given were P0 (basal ration without sinbiotic), P1 (basal ration + sinbiotic 150 ml/kg ration), P2 (basal ration + sinbiotic 300 ml/kg ration), and P3 (basal ration + sinbiotic 450 ml/kg ration). Parameters studied were weight percentage of immune organs and total microbial colonies. The results of this study indicated that the addition of synbiotic isolate Pediococcus pentosaceus strain N6 and fermented cassava peel flour up to a dose of 450 ml/kg as an alternative feed for native chickens increased percentage weight of spleen, thymus, bursa fabrisius, and total microbial colony of super native chickens.

Foraging Activities, Environmental Factors, and Increment Weight of Tetragonula biroi Colonies in Beekeeping with Different Hive Materials

Tetragonula biroi is one of the stingless bee species that has many benefits for human life besides producing honey, propolis, and 13 derivative products. Another important service provided by this bee is as a plant pollinator. This research aims to determine the relationship between the foraging activity of T. biroi bees, environmental factors, and colony development in hives made of different materials. The study was conducted in Rompegading Village, Maros Regency. This research method used a completely randomized design consisting of four different hive materials, namely glass, triplex, cement, and tree hollows, and each treatment was repeated three times. Parameters observed were the number of worker bees leaving and entering the hive throughout the day, colony weight gain, and environmental factors (temperature, humidity, and light intensity). The results showed that the highest foraging activity of worker bees and colony weight gain occurred in natural hives (tree hollows) in the fourth week of observation and in artificial hives made from cement materials. The peak of bee activity entering and leaving the hive occurred in the morning from 07:00–10:00 and in the late afternoon from 13:00–16:00. In the morning, more bees leave the hive, while more enter in the afternoon. Factors such as temperature, humidity, and light affect the foraging activity of worker bees.

Quantifying the impact of an invasive hornet on Bombus terrestris colonies

The invasive hornet Vespa velutina nigrithorax is considered a proliferating threat to pollinators in Europe and Asia. While the impact of this species on managed honey bees is well-documented, effects upon other pollinator populations remain poorly understood. Nonetheless, dietary analyses indicate that the hornets consume a diversity of prey, fuelling concerns for at-risk taxa. Here, we quantify the impact of V. velutina upon standardised commercially-reared colonies of the European bumblebee, Bombus terrestris terrestris. Using a landscape-scale experimental design, we deploy colonies across a gradient of local V. velutina densities, utilising automated tracking to non-invasively observe bee and hornet behaviour, and quantify subsequent effects upon colony outcomes. Our results demonstrate that hornets frequently hunt at B. terrestris colonies, being preferentially attracted to those with high foraging traffic, and engaging in repeated—yet entirely unsuccessful—predation attempts at nest entrances. Notably however, we show that B. terrestris colony weights are negatively associated with local V. velutina densities, indicating potential indirect effects upon colony growth. Taken together, these findings provide the first empirical insight into impacts on bumblebees at the colony level, and inform future mitigation efforts for wild and managed pollinators.

Removing temperature drift for bee colony weight measurements based on linear regression model and Kalman filter

Removing temperature drift for bee colony weight measurements based on linear regression model and Kalman filter

Comparison of indoor (refrigerated) versus outdoor winter storage of commercial honey bee, Apis mellifera (Hymenoptera: Apidae), colonies in the Western United States.

Honey bees (Apis mellifera L.) are critical to the pollination of many important crops in the United States, and one crop that demands large numbers of colonies early each year is almonds. To provide adequate numbers of colonies for almond pollination, many beekeepers move colonies of bees to high-density holding yards in California in late fall, where the bees can fly and forage, but little natural pollen and nectar is available. In recent years, high colony losses have occurred in some operations following this management strategy, and alternative approaches, including indoor storage of colonies, have become more commonly used. The current study evaluated colonies kept indoors (refrigerated and/or controlled atmosphere) for the winter compared with those kept outdoors in either Washington or California. Colonies were evaluated for strength (frames of bees), brood area, lipid composition of worker bees, colony weight and survival, parasitic mites (Varroa mites, tracheal mites), and pathogens (Nosema spp.). No differences were found in colony weight, survival, parasitic mite levels, or pathogen prevalence among the treatments. Colonies stored indoors and outdoors in WA had significantly more frames of bees and less brood present after the storage period than colonies stored outdoors in CA. Lipid composition of honey bees stored indoors was significantly higher than colonies stored outdoors in WA or CA. The implications of these findings for overall colony health and improved pollination activity are discussed.

Land use changes associated with declining honey bee health across temperate North America

Urbanization and agricultural intensification continue to reshape landscapes, altering the habitat available to wildlife and threatening species of both economic and conservation concern. The honey bee, Apis mellifera, is a pollinator of economic importance to North American agriculture yet managed colonies are burdened by poor health and high annual mortality. Understanding the factors influencing this species is critical for improving colony health and supporting crop production. We used a nationwide cohort of 638 managed Canadian colonies to study the dominant drivers of colony health and overwintering mortality. We found that fall colony weight—a major predictor of overwintering survival—was strongly associated with landscape composition. Among four broadly defined land cover types, we discovered that urban and forested land covers were the least valuable sources of habitat for colonies, as inferred from fall colony weight measurements. Agricultural land appeared to provide habitat quality of slightly greater value, while herbaceous land cover was most strongly positively associated with fall colony weight. Herbaceous land cover also exhibited an associational effect size which was strongly statistically distinguishable from those of urban and forested land. Our research indicates that recent and ongoing land-use changes exacerbate modern apicultural challenges, and suggests variation in nutrition or floral resource availability plays a major role in modulating honey bee health. Our work highlights the need for additional research investigating whether land use change-associated alterations in floral resource availability increase the potential for resource competition between pollinator species.

Monitoring of hive weight changes in various landscapes

Bee development is determined by the quantity and quality of food resources available in the environment that can be used by bees only to a certain extent. Therefore, this study aimed to evaluate, by means of changes in hive weight, the amount of food collected by honey bees in various landscapes, in relation to meteorological conditions, landscape, and forest structure. The monitored colonies (n = 104) were placed on electronic beehive scales, which provided data about hive weight, temperature, and humidity over two beekeeping seasons. The landscape valuation within a 2 km radius from each beehive was prepared based on digital maps. The seasonal distribution of food resources collected by honey bees was determined based on hive weight changes analysed in 5-day-periods (i.e. pentads). The hive weight changes mainly depended on the observation period and the air temperature. The hive weight increased from April to the last 10 days of June and when the air temperature was over 24 °C. The proportions of agricultural lands and forests, as well as the air humidity, had a small effect on hive weight changes. Continuous monitoring of the weight of honey bee colonies on a large scale showed that honey bees collected food stores in their nests mainly in the spring. Then, they collected a small amount of food, probably due to limited access to food resources from the last 10 days of June until the end of the growing season.

Management practices and seasonality affect stingless bee colony growth, foraging activity, and pollen diet in coffee agroecosystems

Stingless bees are essential pollinators in tropical ecosystems. Yet compared to their temperate zone counterparts, we know very little about how they respond to agriculture-associated land use, or how this effect is modulated by seasonal variation. Coffee, a dominant crop across the tropics, is grown under diverse management practices, making coffee agroecosystems an important context in which to investigate effects of agricultural management on stingless bees. We evaluated the performance and pollen diet of replicated experimental colonies of the stingless bee Scaptotrigona mexicana in three habitats in a coffee-dominated landscape in southern Chiapas, Mexico: a conventional sun coffee farm, a shaded organic coffee farm, and a forest fragment. We asked how habitat and seasonality influenced colony weight, forager activity, and pollen diet over one year. We placed eight experimental colonies in three habitats (three each in coffee farms; two in forest) and monitored them monthly for colony weight and forager activity. We collected corbicular pollen loads from returning foragers and identified pollen morphospecies. We compared performance and diet metrics across habitats and between wet and dry seasons. Colony performance was dramatically worse in the sun coffee farm; all sun coffee colonies died during the study. Colony performance did not differ between shade coffee and forest. Pollen diet richness was lower in the sun coffee colonies, but all habitats shared the same core pollen morphospecies. Across habitats, colony weight and activity and pollen diet richness decreased during the wet season. Our study suggests that conventional sun coffee cannot support stingless bee colonies, likely because of combined effects of agrochemical exposure and floral resource scarcity. By contrast, shade coffee is equivalent to forests in supporting stingless bee colonies.

Foraging distances, habitat preferences and seasonal colony performance of honeybees in Central European forest landscapes

Abstract Unmanaged forest is considered as native habitat of the Western honeybee Apis mellifera and is assumed to provide important pollen and nectar sources. However, resource supply might be spatially and temporally restricted in managed forests and landscape‐scale studies in European forest regions are currently lacking. Capitalizing on a unique communication behaviour, the waggle dance, we investigated honeybee foraging in a deciduous forest region in southern Germany. We analysed 2022 waggle dances performed by bees of 12 colonies placed in the centre of landscapes with varying degree of forest cover (50%–99% at a 2‐km radius) from March to August 2019, thereby identifying foraging distances and habitat preferences over almost an entire foraging season. By connecting dance information with colony weight recordings, we assessed the role of landscape composition and the contribution of different habitat types to colony weight gain. Foraging distances generally increased with the amount of forest in the surrounding landscape pointing to inferior food resources in the forest. Yet, this effect strongly depended on the season and was more pronounced for pollen than for nectar foraging. Even though colonies in forest‐dominated landscapes had to fly further, colony weight was not significantly affected by forest cover. Compared to expectations based on the proportions of different habitats, colonies foraged more frequently in grassland and cropland than in deciduous and coniferous forests, with late summer being an especially difficult period for pollen foraging in forests. During a phase of colony weight gain in early summer, the use of forests for nectar/honeydew foraging was close to the expectation, highlighting forests as an important complementary source of carbohydrates during short periods of the year. Policy implication. The ecological and economic value of managed forest as habitat for honeybees could be significantly increased by the continuous provision of floral resources, especially for pollen foraging. Therefore, we recommend diversifying forest stands with insect‐pollinated trees, permitting secondary successions in forest gaps, and at larger scales, creating forest landscapes with high habitat diversity. This will not only help native, wild‐living honeybees and beekeepers' colonies residing in forest areas but will also foster social bees in general.

Commercial Bombus impatiens colonies function as ecological traps for wild queens

Abstract In response to anthropogenic environmental change, the cues that animals use throughout their lifecycle to optimize fitness may become unreliable, resulting in an ecological trap. Here we investigated whether commercial bumble bee Bombus impatiens colonies managed for early spring crop pollination act as ecological traps for wild nest‐searching Bombus queens by subverting their natural nest usurpation behaviour. An average of 10 dead wild queens were recovered from each standard colony during the 2‐week period of the experiment, but colonies with queen excluders were successful in preventing wild queen deaths. The use of queen excluders did not impact colony performance in terms of resident queen survival, colony reproduction, colony weight gain or worker body size. Sites where wild nest‐searching queens were small had higher rates of failed usurpation, suggesting smaller‐sized queens are disproportionately at risk from failed usurpation. Furthermore, sites where commercial colonies without queen excluders were introduced for spring crop pollination had fewer bumble bee visits to a later‐blooming crop compared to sites without commercial colonies. Synthesis and applications. Our findings reveal a novel mechanism by which commercial colonies can negatively impact wild bumble bee populations and their pollination services. At the same time, we demonstrate a simple and inexpensive risk mitigation tool—a queen excluder—was 100% effective at eliminating this risk without compromising colony performance. Commercial colonies used outdoors during the bumble bee nest‐searching period should be fit with queen excluders to prevent negative impacts on wild pollinator communities and their services.

Bumble bee colony health and performance vary widely across the urban ecosystem.

Urbanization is a global phenomenon that can affect fitness and could challenge the persistence of most species, including wild bee pollinators. Yet, how and which environmental features affect bee health and fitness within the urban ecosystem remain unclear. Here, we placed experimental Bombus terrestris colonies in sites spanning from the edge into a city's core to investigate bumble bee parasitism, foraging behaviour, energetic stress, colony growth and reproductive output. In each site, ambient temperature was recorded, the availability of floral resources was evaluated and landscape heterogeneity was characterized using land-cover maps. We found that Bombus terrestris parasitism levels increased across the season in line with colony growth but were negatively related to the proportion of impervious surfaces surrounding a site. Bombus terrestris foraging trip duration decreased with increasing ecotones (edge density) but, conversely, increased in sites with honey bee hives present. Energetic stress was evaluated as lowered trehalose titre in the haemolymph of returning foragers; stress increased with the proportion of impervious surfaces. Furthermore, our analyses identified ambient temperature to be a strong predictor of Bombus terrestris colony performance in that high ambient temperature reduced colony growth and indirectly the production of sexual offspring (gynes). Our results highlight the importance of ecotones as well as minimizing the intensity of urbanization and urban honey bee beekeeping for bumble bee colony health and foraging behaviour. They also point to the importance of microclimate (i.e. temperature) for bumble bee colony performance and suggest that increasing temperatures could have a negative impact in slowing colony weight gain, and indirectly in reducing colony reproduction.

Penambahan Polen Aren Sebagai Pakan Lebah untuk Meningkatkan Bobot Koloni Lebah Madu Trigona sp.

The aim of this study was to determine the effect of feed supplement in the form of sugar palm pollen on the increase in colony weight of Trigona sp. The study was conducted in Lembah Sari Village, Batulayar District, West Lombok Regency, which lasted for 4 weeks from May 2020-June 2020. Ten honey bee colonies of Trigona sp. were randomly assigned to two treatment groups with five replications each according to a completely randomized design. The treatment without palm pollen was placed differently with a distance of ±600 meters from the treatment using palm pollen and the distance between replicates was ±1 meter. The stages of the research include making the hive, selecting a colony from glodok, moving the colony to the hive, placing the research hive, and placing the palm pollen. The variables observed included the number of pollen cells and colony weights. The results showed that mean values for the number of pollen cells treated without and with palm pollen treatment from weeks 1-4 were 6,2±0,45, 7,0±0,71, 9,0±0,71, 12,2±0,84 and 6,4±0,55, 8,4±1,14, 11,8±0,84, and 15,4±1,14 respectively. While the colony weight for those with or without supplement were 0,15±0,04, 0,29±0,05, 0,44±0,05, 0,64±0,06 and 0,14±0,01, 0,39±0,09, 0,53±0,03, and 0,80±0,08. The average number of pollen formed and the colony weight for those given supplement was significantly higher than those without feed supplement. Thise results indicate the important of providing feed supplement in order to sustain productivity of Trigona sp. 
 

Grassy–herbaceous land moderates regional climate effects on honey bee colonies in the Northcentral US

The lack of seasonally sustained floral resources (i.e. pollen and nectar) is considered a primary global threat to pollinator health. However, the ability to predict the abundance of flowering resources for pollinators based upon climate, weather, and land cover is difficult due to insufficient monitoring over adequate spatial and temporal scales. Here we use spatiotemporally distributed honey bee hive scales that continuously measure hive weights as a standardized method to assess nectar intake. We analyze late summer colony weight gain as the response variable in a random forest regression model to determine the importance of climate, weather, and land cover on honey bee colony productivity. Our random forest model predicted resource acquisition by honey bee colonies with 71% accuracy, highlighting the detrimental effects of warm, wet regions in the Northcentral United States on nectar intake, as well as the detrimental effect of years with high growing degree day accumulation. Our model also predicted that grassy–herbaceous natural land had a positive effect on the summer nectar flow and that large areas of natural grassy–herbaceous land around apiaries can moderate the detrimental effects of warm, wet climates. These patterns characterize multi-scale ecological processes that constrain the quantity and quality of pollinator nutritional resources. That is, broad climate conditions constrain regional floral communities, while land use and weather act to further modify the quantity and quality of pollinator nutritional resources. Observing such broad-scale trends demonstrates the potential for utilizing hive scales to monitor the effects of climate change on landscape-level floral resources for pollinators. The interaction of climate and land use also present an opportunity to manage for climate-resilient landscapes that support pollinators through abundant floral resources under climate change.

A Comparison of Springtime Pollen and Nectar Foraging in Honey Bees Kept in Urban and Agricultural Environments

Spring is an essential time for honey bee foraging in temperate climates. This is a period of increased brood rearing supporting colony growth and demands access to high-quality pollen and nectar resources. With the expansion of urban and agricultural landscapes, the availability of pollen and nectar producing flowers is declining in many areas. We aim to determine how patterns of spring pollen and nectar foraging differ between colonies surrounded by varying degrees of urban and agricultural intensity, as well as to assess the potential for nectar sampling to serve as a proxy for pollen collection. Thirteen apiaries in Central Ohio, along a gradient of urban and agricultural intensity, were monitored in spring of 2019 through the periodic collection of pollen and nectar samples and continuous colony weight monitoring. We found that spring honey bees in urban and agricultural areas gain comparable amounts of weight and use similar spring resources. Foraging was heavily focused on flowering trees and shrubs including Malus (apple), Salix (willow), and Prunus (cherry), until the beginning of clover bloom (Trifolium spp.). We also identified differences in pollen and nectar foraging within colonies, with nectar containing fewer species collected more evenly than matched pollen samples. These results demonstrate that honey bees in both agricultural and urban environments exhibit similar foraging patterns during the spring, and that plant species important for nectar collection are substantially different from plants important for pollen foraging, though limitations in nectar collection hinder our ability to draw definitive comparisons of pollen and nectar foraging in this region.